MP20051 Low Noise, High PSRR, 1A Linear Regulator

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The Future of Analog IC Technology DESCRIPTION The MP20051 is a low-dropout linear regulator that supplies up to 1A current with a 140m dropout voltage. The externally-adjustable output voltage has a range of 0.8 to 5 from an input voltage of 2.5 to 5.5. An internal PMOS pass element allows for a low 110μA ground current, making the MP20051 suitable for battery-powered devices. Other features include low-power shutdown, and shortcircuit and thermal protection. The MP20051 is available in 3mm x 3mm 8-pin QFN and SOIC8E packages. FEATURES MP20051 Low Noise, High PSRR, 1A Linear Regulator Up to 1A Output Current Low 140m Dropout at 1A Low 110μA Ground Current Output oltage Available from 0.8 to 5 Low Noise: 13μ RMS typical (10Hz to 100kHz) 63dB PSRR @1kHz Stable with Ceramic Capacitor Excellent Load/Line Transient Response Current Limiting and Thermal Protection Available in 3mm x 3mm 8-pin QFN and SOIC8E Packages APPLICATIONS Notebook Computers Cordless Telephones Cellular Phones Wireless Communication Equipment Hand-Held Instruments All MPS parts are lead-free and adhere to the RoHS directive. For MPS green status, please visit MPS website under Quality Assurance. MPS and The Future of Analog IC Technology are Registered Trademarks of Monolithic Power Systems, Inc. TYPICAL APPLICATION R1 OUT 0.8 (1 )olts R2 MP20051 Rev.1.2 www.monolithicpower.com 1

ORDERING INFORMATION Part Number Package Top Marking MP20051DQ* QFN-8 (3mm x 3mm) See Below MP20051DN** SOIC8E See Below * For Tape & Reel, add suffix Z (e.g. MP20051DQ Z); For RoHS Compliant Packaging, add suffix LF (e.g. MP20051DQ LF Z) ** For Tape & Reel, add suffix Z (e.g. MP20051DN Z); For RoHS Compliant Packaging, add suffix LF (e.g. MP20051DN LF Z) TOP MARKING (MP20051DQ) ABR: product code of MP20051DQ; Y: year code; LLL: lot number; TOP MARKING (MP20051DN) MP20051: product code of MP20051DN; MPS: MPS prefix: Y: year code; WW: week code: LLLLLLLL: lot number; MP20051 Rev.1.2 www.monolithicpower.com 2

PACKAGE REFERENCE TOP IEW TOP IEW OUT 1 8 IN OUT 1 8 IN OUT 2 7 IN OUT 2 7 IN FB 3 6 NC FB 3 6 NC GND 4 5 EN GND 4 5 EN EXPOSED PAD ON BACKSIDE CONNECT TO GND QFN-8 (3mm x 3mm) ABSOLUTE MAXIMUM RATINGS (1) IN, EN, FB to GND... -0.3 to +6 OUT to GND... -0.5 to ( IN + 0.5) Continuous Power Dissipation... (T A =25 C) (2) QFN8 (3x3mm)... 2.0W SOIC8E... 2.0W Junction Temperature... 150C Storage Temperature Range... -65 C to 150 C Lead Temperature (Soldering, 10sec)... 260 C ESD SUSCEPTIBILITY (3) HBM (Human Body Mode)... 2k MM (Machine Mode)... 200 Recommended Operating Conditions (4) Supply Input oltage... 2.5 to 5.5 Enable Input oltage... 0 to 5.5 Operating Junction Temp. (T J ). -40 C to +125 C EXPOSED PAD ON BACKSIDE CONNECT TO GND SOIC8E Thermal Resistance (5) θ JA θ JC QFN-8 (3mmx3mm)... 50... 12... C/W SOIC8E... 50... 10... C/W Notes: 1) Exceeding these ratings may damage the device. 2) The maximum allowable power dissipation is a function of the maximum junction temperature T J (MAX), the junction-toambient thermal resistance θ JA, and the ambient temperature T A. The maximum allowable continuous power dissipation at any ambient temperature is calculated by P D (MAX) = (T J (MAX)-T A )/θ JA. Exceeding the maximum allowable power dissipation will cause excessive die temperature, and the regulator will go into thermal shutdown. Internal thermal shutdown circuitry protects the device from permanent damage. 3) Devices are ESD sensitive. Handling precaution recommended. 4) The device is not guaranteed to function outside of its operating conditions. 5) Measured on JESD51-7, 4-layer PCB. MP20051 Rev.1.2 www.monolithicpower.com 3

ELECTRICAL CHARACTERISTICS IN = +0.5 or IN =2.5, EN= IN, Typical values are at T A =25 C, unless otherwise specified Parameter Condition Min Typ Max Units Input oltage 2.5 5.5 Input Under oltage Lockout IN rising 1.95 2.25 Hysteresis of ULO 160 m FB oltage =0.8, =1mA 0.784 0.8 0.816 Output oltage Accuracy =1mA, T A =25 C -2 2 =1mA, -40 T A 85 C -3 3 % Maximum Output Current Continuous, IN 2.5, =2.5 1 A Dropout oltage Short-Circuit Current Limit =0, IN 2.5 1.6 A In-Regulation Current Limit =2.5, within 4% of normal output voltage IN =5.5 1.4 2.2 3.0 A Ground Current =0.1mA, =2.5 110 =1A, =2.5 600 μa =750m, =2.5 105 210 m (6) =1A, =2.5 140 280 =500mA, =2.5 70 140 Line Regulation (7) =2.5, IN from +0.5 to 5.5, =100mA, -0.15 0.15 %/ Load Regulation (8) from 100mA to 1A, =2.5 0.3 % Output oltage Noise =100mA, f ranges OUT =1.1 13 from 10Hz to 100kHz OUT =3.3 35 =5 55 f=100hz 65 PSRR IN = 2.5, = 1.1, = 1A db f=1khz 63 f=10khz 63 f=1mhz 33 Shutdown Supply Current IN =+5.5 0.2 μa EN Pin Current, Enabled IN = EN =+5.5 0.2 μa Feedback Pin Current IN =+5.5, FB =6 0.02 μa Startup Time OUT(NOM) =2.5, C OUT =4.7μF, 45 μs =0% to 90%(NOM) EN Logic High 1.5 EN PIN Threshold EN Logic Low 0.4 Thermal Shutdown Temperature Typical thermal hysteresis =20 C 150 C Notes: 6) Dropout oltage is defined as the input to output differential when the output voltage drops 100m below its nominal value. OUT 7) Line Regulation= IN(MAX) OUT IN MAX IN(MIN) IN(MIN) OUT(NOM) (% / ) μ RMS 8) Load Regulation= OUTI OUT(MAX) OUTI OUT(MIN) OUT NOM (%) MP20051 Rev.1.2 www.monolithicpower.com 4

PIN FUNCTIONS Pin # Name Pin Function 1, 2 OUT 3 FB Regulator output. Bypass with a standard 4.7μF ceramic capacitor to GND. Connect all the pins together externally. Feedback Input. Connect FB to the center point of the external resistor divider. The feedback threshold voltage is 0.8. 4 GND Exposed pad Ground. Connect exposed pad to GND plane for optimal thermal performance. 5 EN Regulator Enable Control Input. Drive EN above 1.5 to turn on the MP20051. Drive EN below 0.4 to turn it off. Do not float the EN pin. 6 NC No Connection. Leave this NC pin open. 7, 8 IN Regulator Input. Supply voltage ranges from 2.5 to 5.5. Bypass with 2.2μF capacitor. These pins must be externally connected for proper operation even if they are internally connected. MP20051 Rev.1.2 www.monolithicpower.com 5

TYPICAL PERFORMANCE CHARACTERISTICS IN = 2.5, = 1.1, C IN =2.2µF, C OUT =4.7µF, T A = 25 C, unless otherwise noted. Quiescent Current vs. Temperature =0A 140 120 100 80 60 40 20 0-40 -20 0 20 40 60 80 100 Quiescent Current vs. Input oltage =0A 160 140 120 100 80 60 40 20 0 3 3.5 4 4.5 5 5.5 6 INPUT OLTAGE() DROPOUT OLTAGE(m) Dropout oltage vs. Temperature =2.5, =1A 200 180 160 140 120 100 80 60 40 20 0-40 -20 0 20 40 60 80 100 DROPOUT OLTAGE(m) Dropout oltage vs. Output Current =2.5 180 160 140 120 100 80 60 40 20 0 0 200 400 600 800 1000 OUTPUT CURRENT(mA) EN () 1.2 1.1 1 0.9 0.8 0.7 0.6 0.5 EN threshold vs. Input oltage EN high threshold EN low threshold 0.4 2.5 3 3.5 4 4.5 5 5.5 INPUT OLTAGE() EN () 0.75 0.7 0.65 0.6 0.55 0.5 0.45 EN threshold vs. Temperature EN high threshold EN low threshold 0.4-40 -20 0 20 40 60 80 100 1.8 Current Limit vs. Temperature 1.8 Current Limit vs. Input oltage Line Regulation =0mA and 100mA 0.3 1.75 1.75 0.2 CURRENT LIMIT(A) 1.7 1.65 1.6 1.55 CURRENT LIMIT(A) 1.7 1.65 1.6 1.55 0.1 0-0.1-0.2 =100mA =0mA 1.5-40 -20 0 20 40 60 80 100 1.5 2.5 3 3.5 4 4.5 5 5.5 INPUT OLTAGE() -0.3 3 3.5 4 4.5 5 5.5 6 INPUT OLTAGE() MP20051 Rev.1.2 www.monolithicpower.com 6

TYPICAL PERFORMANCE CHARACTERISTICS (continued) IN = 2.5, = 1.1, C IN =2.2µF, C OUT =4.7µF, T A = 25 C, unless otherwise noted. 0.20 0.15 0.10 0.05 0.00-0.05-0.10-0.15 Load Regulation -0.20 0 0.2 0.4 0.6 0.8 1 OUTPUT CURRENT(A) Output oltage Accuracy vs. Temperature =0mA 0.20 0.00-0.20-0.40-0.60-0.80-1.00-40 -20 0 20 40 60 80 100 PSRR(dB) 80 70 60 50 40 30 20 10 0-10 PSRR s. Frequency =1A =0.01A =0.5A -20 1.E+01 1.E+03 1.E+05 1.E+07 FREQUENCY(Hz) MP20051 Rev.1.2 www.monolithicpower.com 7

TYPICAL PERFORMANCE CHARACTERISTICS (continued) IN = 2.5, = 1.1, C IN =2.2µF, C OUT =4.7µF, T A = 25 C, unless otherwise noted. Input Power Start Up IN =2.5, =1.1, =1A, with Resistor Load Input Power Shutdown IN =2.5, =1.1, =1A, with Resistor Load EN Start Up EN =2.5, =1.1, =1A, with Resistor Load 500m/div. 500m/div. 500m/div. IN 1/div. IN 1/div. EN 1/div. EN Shutdown EN =2.5, =1.1, =1A, with Resistor Load Line Transient IN =2.5 to 4, =1.1, =10mA, with Resistor Load Line Transient IN =2.5 to 4, =1.1, =1A, with Resistor Load 500m/div. 10m/div. 10m/div. EN 1/div. IN 2/div. IN 2/div. Load Transient IN =2.5, =1.1, =10mA to 1A, with Resistor Load Over Current Protection Steady State IN =2.5, =1.1 10m/div. 500m/div. 500mA/div. IN 1/div. MP20051 Rev.1.2 www.monolithicpower.com 8

FUNCTIONAL BLOCK DIAGRAM Figure 1 Functional Block Diagram MP20051 Rev.1.2 www.monolithicpower.com 9

OPERATION The MP20051 is a low-dropout linear regulator that can supply up to 1A current, which makes it suitable for very low voltage, low quiescent, low noise, and high PSRR applications such as wireless LAN transceivers, notebook computers, smartphones, and other low-power electronics. The MP20051 uses an internal PMOS as the pass element and includes both thermal shutdown and an internal current-limiting circuit. Dropout oltage Dropout voltage is the minimum input to output differential voltage required for the regulator to maintain an output voltage within 100m of its nominal value. Because the PMOS pass element behaves as a low-value resistor, the dropout voltage of MP20051 is only 140m. Shutdown The MP20051 can be switched ON or OFF by a logic input at the EN pin: Logic high turns the regulator on and logic low turns it off. Tie the EN pin to IN if the application does not require the shutdown feature. Do not float the EN pin. Current Limit The MP20051 includes a current limit structure that monitors and controls the PMOS gate voltage to limit the guaranteed maximum output current to 1.6A. Thermal Protection Thermal protection turns off the PMOS when the junction temperature exceeds 150 C, allowing the IC to cool. When the IC s junction temperature drops by 20 C, the PMOS will turn on again. Thermal protection limits total power dissipation in the MP20051. For reliable operation, limit the junction temperature to a maximum of 125 C. Load-Transient Considerations The output response of the load-transient consists of a transient response and DC shift the MP20051 s excellent load regulation effectively limits the DC shift. The output voltage transient depends on the output capacitor s value and ESR. Increasing the capacitance and decreasing the ESR will improve the transient response. MP20051 Rev.1.2 www.monolithicpower.com 10

APPLICATION INFORMATION Setting the Output oltage The MP20051 has an externally-set output voltage with a range of 0.8 to 5 given a 2.5 to 5.5 input. Set the output voltage using a resistive voltage divider from the output voltage to the FB pin. The result of the voltage divider at the FB pin is: FB OUT R2 R1 R2 Where FB is the feedback threshold voltage ( FB = 0.8), and is the output voltage. Thus the output voltage is: R1 R2 0.8 R2 R2 can go as high as 100kΩ, but typical applications use 10kΩ. After selecting R2, R1 is determined by: OUT FB R 1 R2 FB For example, for a 1.1 output voltage, R2 is 10kΩ, and R1 is 3.75kΩ. You can select a standard 3.75kΩ (±1%) resistor for R1. Power Dissipation The power dissipation for any package depends on the thermal resistance of the case and circuit board, the temperature differential between the junction and ambient air, and the rate of air flow. The power dissipation across the device can be represented by the equation: P IN OUT IOUT The allowable power dissipation can be calculated using the following equation: TJunction TAmbient JA P(MAX) / Where (T Junction T Ambient ) is the temperature differential between the junction and the surrounding environment, θja is the thermal resistance from the junction to the ambient environment. Connecting the exposed GND pad to a large ground pad or plane helps to channel away heat. Output Capacitor Selection The MP20051 is specifically designed to work with a standard ceramic output capacitor to save space and improve performance. Use a 4.7µF ceramic capacitor for most applications. Larger output capacitors will improve load transient response and reduce noise at the cost of increased size. MP20051 Rev.1.2 www.monolithicpower.com 11

PACKAGE INFORMATION QFN-8 (3mm 3mm) MP20051 Rev.1.2 www.monolithicpower.com 12

0.189(4.80) 0.197(5.00) 8 5 SOIC8E 0.124(3.15) 0.136(3.45) PIN 1 ID 0.150(3.80) 0.157(4.00) 0.228(5.80) 0.244(6.20) 0.089(2.26) 0.101(2.56) 1 4 TOP IEW BOTTOM IEW SEE DETAIL "A" 0.013(0.33) 0.020(0.51) 0.051(1.30) 0.067(1.70) SEATING PLANE 0.000(0.00) 0.006(0.15) 0.050(1.27) BSC SIDE IEW 0.0075(0.19) 0.0098(0.25) FRONT IEW 0.010(0.25) 0.020(0.50) x 45o GAUGE PLANE 0.010(0.25) BSC 0.024(0.61) 0.063(1.60) 0.050(1.27) 0 o -8 o 0.016(0.41) 0.050(1.27) DETAIL "A" 0.138(3.51) 0.103(2.62) RECOMMENDED LAND PATTERN 0.213(5.40) NOTE: 1) CONTROL DIMENSION IS IN INCHES. DIMENSION IN BRACKET IS IN MILLIMETERS. 2) PACKAGE LENGTH DOES NOT INCLUDE MOLD FLASH, PROTRUSIONS OR GATE BURRS. 3) PACKAGE WIDTH DOES NOT INCLUDE INTERLEAD FLASH OR PROTRUSIONS. 4) LEAD COPLANARITY (BOTTOM OF LEADS AFTER FORMING) SHALL BE 0.004" INCHES MAX. 5) DRAWING CONFORMS TO JEDEC MS-012, ARIATION BA. 6) DRAWING IS NOT TO SCALE. NOTICE: The information in this document is subject to change without notice. Users should warrant and guarantee that third party Intellectual Property rights are not infringed upon when integrating MPS products into any application. MPS will not assume any legal responsibility for any said applications. MP20051 Rev.1.2 www.monolithicpower.com 13